| ObjectiveHigh tibial osteotomy has long been regarded as an effective method for the treatment of single compartment disease(mainly medial compartment)of knee joint.In recent years,many hospitals in China have successively carried out open wedge high tibial osteotomy(OWHTO),and its disadvantages have been gradually reported during this popular period.This study retrospectively explored the relationship between the degree of OWHTO correction and the position of the patella,cartilage and patellofemoral joint degeneration.It was assumed that the development of postoperative patellofemoral joint degeneration was related to the degree of intraoperative deformity correction,and the risk value was inferred.MethodsFrom April 2017 to January 2019,70 patients diagnosed with KOA with varus deformity and treated with open wedge high tibial osteotomy(OWHTO)were included in the study.The knee joint score system(HSS score)of American special surgery hospital was used to evaluate the efficacy.Full-length weight-position X-ray of lower limbs was used to measure the hip-knee-ankle angle(HKA)and medial proximal tibial angle(MPTA)to assess the severity of varus deformity before surgery and the degree of postoperative correction.The preoperative and postoperative changes of HKA and MPTA were compared.The preoperative and postoperative patellar height(PH)was measured by blackburne-peel method,and the preoperative and postoperative changes in PH and PTS were compared.Preoperative and postoperative patel lofemoral articular cartilage was measured by MRI.After comparing the results,patients were divided into the patellofemoral joint plus progression group and the group with no patel lofemoral joint progression,and the parameters between the two groups were compared.The accuracy test(ROC)curve was used to determine the relationship between cartilage changes and changes in medial proximal tibia angle(MPTA)and HKA,to obtain the cut off value,and to calculate sensitivity,specificity,and area under the curve(AUC).The rank sum test was used to analyze the difference in preoperative and postoperative patellofemoral joint status between the two groups.ResultsFinally,49 cases were included in the study,and the postoperative HSS score increased from 59.63±4.69 to 86.47±4.35(P<0.05).After the operation,there were 22 cases of patellofemoral joint plus progression group,among which 10 cases(20.4%)of patellar cartilage deteriorated,14 cases(28.6%)of trochlear cartilage deteriorated,and 27 cases in the group with no progress of patellofemoral joint.Between the two groups of age,gender,BMI,number of limb,the follow-up time,preoperative and postoperative of HSS score、PH and PTS,ΔPTS and Δ PH have no statistical differences(P>0.05),the Δ HKA and Δ MPT A comparison,visible significantly statistical differences between the two groups(P<0.05).ROC curve analysis showed that Δ HKA and Δ MPT A cut off value is 9.69° and 8.99°(P<0.05).AUC of Δ HKA was 0.861(95%CI:0.74-0,98,P<0.05),the sensitivity was 77.3%,the specificity was 88.9%.The AUC of Δ MPTA is 0.919(95%CI:0.83-1.00,P<0.05),the sensitivity was 95.5%,the specificity was 77.8%.ConclusionHigh tibial osteotomy(OWHTO)can lead to postoperative degeneration of patellofemoral cartilage,and the greater the correction,the more likely it is to cause degeneration of the patellofemoral joint.Conclusion by ROC curve,resulting in patellofemoral joint degeneration of cut off value:Δ MPTA=8.99° or Δ HKA=9.69°,when the correct degree is greater than the two value,the postoperative may cause patellofemoral joint degeneration,but did not see a significant decrease in short term knee functional score.In addition,the operation method can lead to the decrease of patellar height and the increase of PTS after operation,but the data show that both of them are not the main factors leading to the degeneration of patellofemoral joint. |
PDF Full Text Request